Born into poverty in Puerto Rico, Daniel Santos became one of the most influential singers and songwriters in Latin and South America during the middle of the century. From the pen of Pedro Flores, his early love-lost lyrics — a series of aching, mostly one-word hits such as "Despedida," "Obsesión," "Irresistible," "Perdón," "Venganza" — influenced author Gabriel García Márquez as much as other singers, while his later, patriotic material riled American intelligence officers and inspired Fidel Castro's Cuban Revolution.